At periodic intervals the Food and Nutrition Board of the Institute of Medicine produces a report entitled the Dietary Reference Intakes (DRI). The recent DRI report for macronutrients (energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids) was published in 2005.1 For each macronutrient, a series of values is published, along with a detailed review of all data used to derive those values. Those values for macronutrients are the estimated average requirement, the recommended dietary allowance (RDA), the tolerable upper intake level, and the adequate intake. Of these terms, the RDA is the most widely recognized and has the greatest influence on daily nutrition practices.